Dispensing apparatus for viscous material



June 1, 1954 A. A. KNEE 2,679,811

DISPENSING APPARATUS FOR VISCOUS MATERIAL Filed Oct. 17, 1951 4 Sheets-Sheet l fig 1 .AA/am/ A. (-55, INVENTOR ATTORNEY June 1, 1954 A. A. KNEE 1 DISPENSING APPARATUS FOR VISCOUS MATERIAL Filed Oct. 17, 1951 I 4 Sheets- Sheet 2 1- /3/ Anew/I. KNEE Ill/l [30 INVENT p o AI-3 a A26 /23 P f1 10 as w BY gal/M ATTORNEYS.

June 1, 1954 KNEE DISPENSING APPARATUS FOR VISCQUS MATERIAL 4 Sheets-Sheet 3 Filed Oct. 17, 1951 INVENTOR.

ATTbRNEYs.

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- 4 Sheets-Sheet 4 A. A. KNEE DISPENSING APPARATUS FOR VISCOUS MATERIAL June 1, 1954 Filed 0ct.'17, 1951 I INVENTOR AAmv/I. (Na:

6 x7 3", r M ATTORNEYS.

Patented June 1, 1954 DISPENSING APPARATUS FOR VISC OUS MATERIAL Aaron A. Knee, Charlotte, N. 0.,

assignor to Lance, Inc., Charlotte, N. 0., a corporation of North Carolina Application October 17, 1951, Serial No.2'51k125 9 Claims.

This invention relates to apparatus for applying a paste or viscous filler or coating, such as peanut butter and the like, to crackers, waters and similar articles and more especially to an improved dispensing apparatus therefor.

This application is a continuation-in-part of my co-pending application, Serial No. 236,617, filed July 13, 1951, and entitled Improved Sandwich Making Machine.

Heretofore, many attempts have been made to perfect a suitable apparatus for depositing coatings of viscous material such as paste, peanut butter and the like, upon wafers, crackers and the like, wherein a coating of substantially uniform thickness, length and width was provided upon each of a plurality of wafers, crackers or the like which were passed beneath the dispensing apparatus in rapid succession. However, many difii culties have been encountered and, particularly, in the instance of peanut butter being used as the filler or coating material, the means heretofore provided on the dispensing means for severing or otherwise separating each portion of the coating material or filler from the bulk of the filler or coating material disposed in the dispensing apparatus has been or such construction that the filling material would tend to cling to the severing means and, since peanut butter is an extremely adhesive material as well as an extremely cohesive material, the peanut butter would tend to cling to the walls of the orifice through which it was dispensed from the dispensing apparatus.

This would not only require stopping the machine at frequent intervals 'for cleaning the dispensing mechanism but would, in some instances, also cause a substantial portion of the filler dispensed through the discharge orifice of the dispensing mechanism to tear apart from the dispensed portion each time the orifice was opened, with the result that the wafer or cracker would only be partially coated with the coating material or filler.

It is, therefore, the primary object of this invention to provide an improved dispensing apparatus for viscous materials, such' as peanut butter and the like, wherein a unique means is provided for parting the viscous material upon predetermined portions thereof being dispensed through the discharge opening or orifice of the dispensing apparatus and wherein the dispensing apparatus has means for directing the viscous material through the discharge openings or orifices thereof under constant pressure.

This unique means for parting the extruded portions of the filler or coating material from the bulk of material disposed within the dispensing apparatus difiers primarily from part ing means heretofore employed in that the size of the opening or orifice through which the material is dispensed is rapidly decreased in size and in its process, the viscous material is compressed at said orifice or opening until the opening is completely closed. This causes the ex truded portions of the viscous material to be tapered slightly at the trailing edges thereof and to be parted from the bulk of the viscous material by squeezing or compressing the viscous material at the juncture of the extruded portion thereof and the bulk thereof or at the opening or orifice. I

It is another object of this invention to provide an improved dispensing apparatus adapted to be associated with a machine having a conveyor thereon for successively moving wafers or crackers beneath the dispensing apparatus, the dispensing apparatus being in the form of a gear pump having a cavity or chamber therein adapted to contain a supply of viscous material, such as peanut butter and the like, and being also provided with a discharge opening or orifice which is normally closed by a vertically movable gate member. Suitable passageways are provided in the gear pump and suitable gears therein direct the viscous material underpressure to the discharge opening or orifice. The pump is also provided with other passageways for directing or circulating the viscous material back into the chamber from whence it came when the gate is in a closed position.

A relatively thin member or plate defines the bottom of the passageway which directs the viscous material from the chamber to the discharge opening or orifice and means are provided for directing the cracker or wafer closely beneath said relatively thin member or plate. One edge of said plate also defines the bottom of said discharge opening or orifice and when the gate is" in a closed position, the fiat lower surface thereof engages the upper surface of said plate and the exterior surface or the gate is flush withthe corresponding vertical edge of the relatively thin member or plate. Means are provided for raising or opening the gate at predetermined intervals, whereupon the viscous material is forced out of the dispensing apparatus through the opening defined by the lower edge of the gate and the upper surface of the relatively thin member or plate and, upon a predetermined length of the viscous material being extruded through said opening, the gate is permitted to move downwardly and, in so doing, this gate squeezes or compresses the viscous material against the upper surface of the bottom or relatively thin member or plate to ultimately part the length of extruded viscous material from the viscous material in the passageway leading to the discharge opening or orifice.

This not only causes the viscous material to be cleanly parted but since the wafer or cracker is disposed in very close proximity to the lower edge of said gate, the viscous material is not separated or parted with a ragged or rough edge and, consequently, does not adhere to the exterior edges of the discharge opening or orifice defined by the proximate surfaces of the gate and the relatively thin member or plate.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds when taken in connection with the accompanying drawings, in which- Figure 1 is a fragmentary elevation of a portion of a sandwich making machine of the type shown in said co-pending application and showing the improved filler or coating dispensing apparatus mounted thereon;

Figure 2 is an enlarged top plan View of the central portion of Figure 1 showing the improved filler or coating dispensing apparatus but omitting the hopper and the conveyor therefrom for purposes of clarity;

Figure 3 is an enlarged longitudinal vertical sectional view through the improved dispensing apparatus taken substantially along the line 3-3 in Figure 2, but showing the gears and gate latch in elevation, and showing portions of the wafer or cracker propelling means in association there with schematically, and also showing the manner in which the hopper is secured to the upper surface of the filler or coating dispensing apparatus;

Figure 4 is an isometric view of the filler or coating dispensing apparatus disassociated from the sandwich making machine and with many of the parts omitted for purposes of clarity;

Figure 5 is a fragmentary isometric View showing the manner in which the gates are mounted but omitting the main body portion or housing of the gear pump;

Figure 6 is an enlarged detail of the latching means shown in the upper right-hand portions of Figures 1 and 3 but showing the same in a different position;

Figure 7 is an enlarged sectional plan view through the dispensing apparatus taken substantially along the line 'I-? in Figure 1 but omitting the latch means and the means for driving the gears of the gear pump;

Figures 8, 9 and 10 are detailed views of the lower right-hand portion of Figure 3 showing the gate in successively lowered positions and illustrating the manner in which the extruded viscous material is parted as it is deposited upon a wafer, cracker or the like.

Although the dispensing apparatus is shown in the form of a gear pump, it is to be understood that means other than gears may be provided for directing the viscous material, such as peanut butter and the like, to the discharge opening or orifice of the dispensing apparatus. Referring to Figures 1, 2, 3 and 8 to 10, inclusive, there is shown a portion of a wafer or cracker coating machine or sandwich machine, the frame of which is broadly designated at H]. This sandwich machine or wafer coating machine may be of any desired construction and is shown as being substantially of the type shown in my said co-pending application, Serial No. 236,617. A similar machine is also shown in my co-pending application, Serial No. 777,083, filed September 30, 1947, and entitled Sandwich Making Machine, now Patent No. 2,603,341, issued July 15, 1952. Since the machine illustrated in association with the present dispensing apparatus is clearly disclosed in said co-pending application, Serial No. 236,617, only so much of the machine is shown in the annexed drawings as is deemed'necessary to a clear understanding of the present invention.

In this instance, the frame l 0 comprises transversely spaced upper horizontally disposed side frame members H and i2 which are spanned by longitudinally spaced transverse track supporting bars i3, i4 and IS. The bars [3, l4 and I5 are spaced above the upper surfaces of the longitudinally extending side frame members II and I2 by respective pairs of spacing members, bars 01' supports it, I1 and IS. The supports it are secured to the upper surfaces of the frame members ii and I2, by any suitable means such as screws 2!, and the supports I! and 18 are penetrated by respective screws 22 and 23 which also penetrate the respective transverse bars i i and i5 for securing these bars I 4 and I5 and the supports I! and [8 to the upper surfaces of the longitudinally extending frame members H and 2.

The transverse bar I3 is secured between the upper portions of the supports 15, by any suitable means such as screws 24, only one of which is shown in Figure 1. The transverse Jar i3 supports a suitable wafer or cracker dispensing n1echanism or magazine broadly designated at 25 which has suitable means including a connecting rod 25 for discharging cakes, crackers or other wafers therefrom one at a time onto a suitable conveyor broadly designated at 2?.

This wafer dispensing apparatus 25 may be identical to the wafer dispensing mechanism shown in said co-pending application, Serial No. 236,617, and a detailed description thereof is deemed unnecessary. The convey mechanism or magazine 2! is preferably an endless type of conveyor comprising a pair of spaced endless carrier chains or endless belts 39 and 3! driven by conventional means, not shown, to move from left to right in Figure 1 in timed relation to the rate at which the wafers, crackers or the like are dis charged from the wafer dispensing mechanism 25.

The chains 36 and 3! are bridged by a plurality of equally spaced transversely extending conveyor bars Mil suitably secured thereto which are caused to move along in a straight path in parallel relation to the longitudinally extending frame members H and !2 by suitable means not shown in the present drawing but being clearly shown in said co-pending application, Serial No. 236,617. The sandwich making or wafer coating machine shown in the drawings is designed for conveying two rows of crackers, wafers or the like along the trackways thereof to be presently described. It is to be understood, however, that the present filler dispensing apparatus may be associated with a machine having a lesser or greater number of trackways for conveying a lesser or greater number of rows of crackers, wafers and the like through the machine, as desired.

Since the portion of the conveyor 2"! shown in Figures 1 and 7 may be construed as the upper reach of an endless conveyor, there is fixedly mounted in each of the bars 32 and extending radially therefrom two pairs of relatively closely spaced main conveyor pins or prongs 33, 34 and 33', 34'. It is to be understood that each of the sets of main conveyor pins are arranged in rights and lefts, which is also the manner in which the trackways corresponding thereto to be later described are arranged.

Now, as the pins 33 and 34 move with the upper reaches of the conveyor carrier chains 30 and 3|, they move along a trackway broadly designated at 35 while the pins 33 and 34' move along a trackway broadly designated at 35. These trackways 35 and 35' may be identical to the trackways |52 and I52 shown in said copending application, Serial No. 236,617, and, therefore, only a general description thereof will now be given. Since the trackways 35 and 35 are identical, only the trackway 35 will be described and those parts of the trackway 35' which are identical to the parts associated with the trackway 35 will bear the same reference characters with the prime notation added.

The trackway 35 comprises a middle track 35, and outside tracks 37 and 3B which extend longitudinally of the machine. The outside tracks 3? and 38 are spaced from the middle track I53. It will be observed in Figure 7 that the outside tracks 37 and 33 are spaced so the pins 33 and 35 of the main conveyor 27 move between the out side tracks 37 and 38 and the middle track 35 and in closely spaced relation to the proximate surfaces of the tracks 37 and 38. These tracks 36, 31 and 38 are suitably supported by and depend from the transverse bars M and I5 and by other means clearly shown in said c0-pending application, Serial No. 236,617.

The transverse bars l4 and Hi also serve to support transversely spaced longitudinally extending trackway guides 4| and 42 spaced from the outer vertical surfaces of the outside tracks 31 and 38. The upper edges of the trackway guides 3| and 42 are generally disposed at higher elevations than the upper edges of the relatively thin tracks 33, 37 and 38. The upper edges of the tracks 36, 37 and 33 are of identical configuration throughout their lengths with respect to each other and the trackway guides 4| and 32 are of identical configuration throughout their lengths with respect to each other. The upper ends of the pins 33 and 34, in the upper reach of the conveyor 37, project above the horizontal plane of the tracks 35, 37 and 38 and generally are disposed at a lower elevation than the upper edges of the trackway guides 4| and 42 to thereby propel crackers, wafers or the like, indicated at W, from left to right along the upper surfaces or edges of the tracks 35, 37 and 38, the trackway guides 4| and 42 being spaced according to the width of the wafer W.

It is to be noted in Figures 3, 8, 9 and 10 that the upper edges of the tracks 36, 31 and 38' are disposed in closely spaced relation to the lower surface of the improved filler dispensing apparatus to be presently described. As heretofore stated, the connecting rod 26 operates in timed relation to movement of the conveyor 21 from left to right in Figure l to cause wafers W to be discharged therefrom one at a time and these wafers fall onto the tracks 35, 37 and 38 between the trackway guides 4| and 42 in advance of each of the sets of conveyor pins 33 and 34 moving beneath the magazine or wafer dispensing mechanism 25 to thus cause the wafers W to move past the discharge end of the filler dispensing apparatus in rapid succession.

Filler dispensing apparatus Assuming that the main conveyor 27 moves in a forward direction as it moves from left to right in Figure 1, there is disposed forwardly of the magazine or wafer dispensing mechanism 25 a filler or viscous material dispensing apparatus comprising a housing or body portion broadly designated at 50, which may also be termed a gear pump. For purposes of assembly, the housing 53 is made in sections or blocks each preferably being of cast construction and comprising outside or end blocks 5| and 52 of substantially L-shaped configuration and between which are disposed intermediate blocks 53 and 54 and a center block 55. If a single trackway is used, it is evident that the center block 55 and one of the intermediate blocks could be omitted and the two outside blocks 5| and 52 could abut against the opposite sides of the remaining intermediate block.

During maintenance of the filler dispensing apparatus, it may become necessary to disassemble these blocks 5| to 55, inclusive, for cleaning or other purposes and, since it is necessary that all of the blocks are held in precise alinement with each other, the blocks 5| to 55, inclusive, are collectively penetrated by dowel shafts or rods 56 and 57 (Figures 1 and 3) and are removably secured together by a plurality of bolts 63 which also collectively penetrate the blocks 5| to 55, inclusive, there being four of these bolts 50 shown in Figure 3. A relatively thin member or plate 3|, which may be construed as the base of the filler dispensing apparatus, is suitably secured to the lower surfaces of the blocks 53 to 55, inclusive, collectively as by screws 62. It will be observed in Figure 3 that the plate or base 3| extends substantially beyond the front vertical surfaces of the blocks 5| to 55, inclusive, for purposes to be later described.

Since the housing 5|! is preferably of less overall width than the distance between the side frame members II and 52 of the frame It, it will be observed in Figures 2, 3, 4 and 7 that the outer portions of the bottom plate or base 5| are secured to the upper surfaces of transversely spaced longitudinally extending support or adaptor plates 63 and 54, by any suitable means, such as screws 65 which are threadably embedded in the out side or end blocks 5| and 52 of the housing 50. These plates 63 and 54 project outwardly substantially beyond the outer surfaces of the end blocks 5! and 52 and are suitably secured, as by bolts or screws 63 to the upper surfaces of suitable spacing members 61 which are slidably penetrated by the screws 65. The screws 56 are threadably embedded in the side frame members II and |2 to thus secure the respective adaptor plates 53 and 55 to the respective frame mentbers H and I2 of the frame It).

The spacing members 51 are provided in order to space the base or plate 6| above the frame i l surhciently so that the upper surfaces of the tracks 35, 3'5 and 33 are disposed in closely spaced relation to the lower surface of the plate 35 as is clearly shown in Figure 3. The displacement between the upper edges of the tracks 33, 3'5 and 33 and the bottom of the plate 5| is slightly greater than the thickness of the crackers or wafers W. It will be noted that this bottom plate 6| is also spaced to provide clearance for movement of the conveyor pins 33, 33, 33' and 35 therebeneath as is clearly shown in Figure 3.

Now, referring to Figures 3 and 4, it will be observed that the intermediate and center blocks 53 to 55, inclusive, of the housing 53 are cut away to provide front and rear inner vertical surfaces 7 I5, I2 and I4, respectively, which define the front and rear walls of a cavity broadly designated at I6. The side walls of the cavity 16 are defined by the inner or proximate surfaces of the outside or end blocks BI and 52.

The center block 55 has a horizontal upper surface I? which defines the bottom of the corresponding portion of the cavity 76. However, the portions of the cavity I6 defined by the intermediate blocks 53 and 54 are of greater depth than the surface 1! of the center block 56 and each of the intermediate blocks 53 and 54 has a pair of arcuate cavities 85 and 8! therein which conform to the curvature of suitable pairs of intel-meshing gear wheels 82 and 83, respectively (Figures 2 and 3). These gear wheels 82 and 83 may be of any desired type, however, it is preferable that helical gears be employed. The gears 82 are each fixedly mounted, as by a key 84, on an enlarged medial portion 85 of a common drive shaft 86 which has reduced end portions 81 integral therewith.

It will be observed in Figure? that the enlarged medial portion B5 of the drive shaft 86 penetrates the center block 55 and opposite ends of this enlarged medial portion 85 terminate in sliding engagement with the proximate surfaces of the outside blocks 5! and 52. The reduced end portions 8'! of the shaft 86 penetrate the outside or end blocks 5| and 52, in which they are rotatably mounted, and each of the end blocks 5I and 52 has a boss portion 90 projecting outwardly therefrom on which a gland member EI is threadably mounted. This gland member SI holds a sealing member 92 against the outer end of the corresponding boss portion 95. The reduced portions 87 of the shaft 86 penetrate the corresponding boss portions 90, the sealing members 92 and the gland members 9| and also rotates therein.

The drive shaft 85 may be driven in any desired manner and is shown in Figures 1 and 2 as being driven in substantially the manner shown in said co-pending application, Serial No. 236,617. In this instance, each of the reduced portions 3? of the drive shaft 81 has a sprocket wheel 94 fixed thereon which is engaged by a sprocket chain 55. The sprocket chain 95 extends downwardly and also engages a sprocket wheel 96 which is fixed on a driven shaft 97 which may be driven in the manner shown in said lastnamed co-pending application.

In order to insure that the sprocket chain 95 is held under proper tension at all times, the sprocket chain 95 is engaged by a take-up sprocket wheel I50 which is rotatably mounted on one end of an arm IDI fixedly secured, as by a screw I52, to a block I53. The block I03 is suitably secured to the lower surface of the corresponding side frame members i I and !2, as by screws I54. Since the driven shaft 9'! may be supported for rotation and driven in any desired manner, such as the manner shown in said copending application, Serial No. 236,617, a further description thereof is deemed unnecessary.

Referring again to Figure 7, it will be observed that the gear wheels 83 mesh with the corresponding gear wheels 32 and each of the gear wheels 83 is fixedly mounted on an enlarged medial portion I61 of a shaft I08. Each of the shafts I58 has a reduced end portion I09 at each end thereof. The proximate or inner end portions I59 of the shafts I08 are rotatably mounted in the center block 55 and the outer end portions I 09 of the shafts I08 are rotatably mounted 8 in the corresponding outside or end blocks BI and 52.

It might be stated that, for best results, it is preferable that the shafts 86 and I08 are spaced accurately with respect to each other to insure that the pitch diameters of the gear wheels 82 and 83 properly coincide and to insure that there is a minimum of clearance between the gear wheels 82 and 83 and the corresponding arcuate cavities and SI to thereby insure that the viscous material will not solidify or congeal between the gear wheels 82 and 83 and. the respective cavities 35 and 8|. This is particularly important when peanut butter is used as the coating or filling material because the compressed peanut butter would ultimately freeze" the gears against further rotation, otherwise.

Each of the intermediate blocks 53 and 54 of the housing 58 has a vertically extending bore or passageway H0 in the center thereof which is flared outwardly at its top portion to properly direct the filling material downwardly as the proximate portions of the mating gears 82 and 33 move downwardly in Figure 3. Thus, the viscous filling material is forced downwardly through the bore or passageway III] and into a passageway HI which extends forwardly to the discharge end of the housing 50. It will be noted that the bottom of this bottom passageway III is defined by the bottom plate 6| and each of the intermediate blocks 53 and 54 is cut away to form the top wall of the passageway H I while opposed sides of the passageway III are defined by the proximate surfaces of the center block 55 and the corresponding outside or end blocks EI and 52.

The front end of each of the blocks 5| to 55, inclusive, of the housing 50 has a forwardly projecting portion H2 thereon and there is secured to the front vertical surface of these portions II2, collectively, a gate support block or plate H3. This gate support block II3 may be integral with the blocks 5I to 55, inclusive, however, for simplicity of manufacture, it is preferable that a separate block be employed and the manner in which this block H3 is secured to the blocks 5I to 55, inclusive, will be later described.

The gate support block II3 has a passageway II4 in the inner or rear face thereof which communicates with the lower or bottom passageway III in each of the blocks 53 and 54 and which also communicates with a passageway H5, in the corresponding block 53 or 54, which is shown as being substantially Z-shaped in Figure 3. This passageway H5 extends upwardly and defines a return opening H5 in the front wall of the cavity I6 immediately above each of the front gear wheels 82 or at least above the points at which the front gear wheels 82 enter the corresponding cavity 83 in the blocks 53 and 54.

The upper horizontal and vertical branches of the passageway I I5 may be formed by drilling through each of the intermedaite blocks 53 and 54 of the housing 55 and, therefore, suitable plugs I20 and I2I are secured in each of the blocks 53 and 54 as by a pressed or sweat fit, to thus seal the upper horizontal and the vertical branches of the passageway I I5.

The gate support block II3 has a discharge opening I22 in the bottom edge thereof coinciding with the groove III in each of the intermediate blocks 53 and 54. Thes discharge openings I22 are normally closed by vertically disposed relatively thin gates I23 and I23. The gate I23 is disposed immediately above the trackway 35 and the gate I23 is disposed above the trackway 35. Although, gates of slightly varying thickness may be employed, it has been found most favorable that the material from which each of the gates I23 and I23 is made should be a relatively hard steel, approximately 3% thick. When more than one gate is employed, as is the case in the present instance, all of the gates should be accurately ground to a uniform thickness in order to insure that the gates may slide easily in a vertical plane while, on the other hand, insuring that the pressure of the peanut butter or other viscous filling material against the lower portion of the gate, when the gate is in a closed position as shown in Figure 3, will not cause the peanut butter or other viscous filling material from seeping past the edges of the corresponding gates I23 and I23.

There are many different ways in which the gates I23 and I23 maybe supported for vertical movement against the gate support plate II3. However, it is preferable that suitable spacing or guide plates I25 be disposed adjacent opposite s de edges of the gates I23 and I23 and that these gate guide plates I25 should not be over m thicker than the gates I23 and I23. The gates I23 and I23 are held against the front or outer surface of the gate support plate or block I I3 by means of a gate confining plate I26 which is suitably secured to the front surfaces of the gate guide plates I25 by screws I2'I.

The screws I21 slidably penetrate the corresponding gate guide plates I25 and are threadably embedded in the forwardly projecting portions I I2 of the corresponding outside and center blocks i, 52 and 55. It will be noted that the upper edges of the plates II3, I25 and I26 terminate in substantially the same horizontal plane and in substantially the same horizontal plane as the upper surfaces of the forwardly projecting portions N2 of the blocks 5I to 55, inclusive.

Although the lower edges of the plates I I3 and I25 are disposed in engagement with the upper surface of the corresponding portion of the base plate (ii, the lower edge of the gat confining plate I23 is spaced above the lower edges of the plates II3 and I25 to thereby permit the filling material to pass between the upper surface of the base plate 3i and the lower edges of the corresponding gates I23 and I23 when the gates are in raised or opened position. Of course, the size of the discharge openings are determined by the displacement between th lower edges of the gates I23 and I23 and the upper surface of the plate 6i. Since the gate guide plates I25 must be positioned accurately with respect to each other to insure that the gates I23 and I23 slide in snug engagement therewith, it may be desirable to mount the gat guide plates I25 on the gate support plate H3 by means of dowel pins or the like and to provide holes for the screws I21 of slightly larger diameter than the screws I21 in the gate 525 for securing the gate assembly shown in Figure 5 to the front surfaces of the projections II2 on the blocks 5! to 55, inelusive, of the housing.

The most important feature of the present invention is that the bottom edge of each of the gates I23 and IE3 is not sharp but is perfectly hat and engages the perfectly flat upper surface of the base plate SI of the housing 53 when in closed position and the front surface of each of the gates I23 and I23 is disposed either flush with the front edge of the plate 6| or the lower edges of each of the gates I23 and I23 may project very slightly beyond the front edge of the plate SI. However, th amount that each of the gates I23 and I23 may project beyond the front edge of the plate SI when these gates are in closed position must not be any greater than is absolutely necessary and should not be over one or two thousandths of an inch.

Each of the gates I23 and I23 has secured therein, as by a pressed fit, and projecting forwardly therefrom, a spring anchor I33, to which the upper end of a tension spring [BI is connected. This tension spring I3I extends downwardl and its lower end is connected to a spring anchor I330: suitably secured in th gate confining plate IZ as by a pressed fit. Thus, the springs I3I normally urge the corresponding gates I23 and I23 downwardly to closed position in engagement with the upper surface of the base plate 6 I.

Sinc the gates are opened and closed in rapid succession, it will be noted that the front or foremost portion of the base plate IN is secured to the lower surface of the gate support block or plate I I3 by screws I32 in order to insure that the front portion of this base plate 6I will not bend downwardly or vibrate with the constant pounding of the gates I23 and 523 during operation of the sandwich making or Wafer coating machine. In Order to raise the gates I23 and I23 in timed relation to movement of the main conveyor, and to permit the gates to be moved downwardly by the corresponding springs I3I, the gates I23 and I23 have respective slots or openings I33 and I32 in the exposed upper portions thereof which are preferably rectangular in shape and which are engaged by respective latch members I35 and I35. Since these latch members I35 and I35 are mounted in an identical manner, only the latch member I35 will be described in detail and those parts associated with the latch member I35 will bear the same reference characters with the prime notation added.

The latch member I35 is shown in operative position in Figures 1, 2 and 3 and is shown in inoperative position in Figure 6. The pivoted latch I35 is preferably in the form of an elongated rigid member having a cavity I36 in the lower portion thereof defining a hook I31 on the lower end of the pivoted latch I35. The depth of this notch I35 is preferably equal to the thickness of the gate I23 and the height of the notch I36 is preferably substantially greater than the distance between the upper wall of the slot or opening I33 and the upper surface of the gate I23.

The upper portion of the pivoted latch I35 is fixedly mounted on a pin I33 pivoted in the outer or free end of a latch holder block MI provided with a groove I 32 at the outer end thereof and in which the upper portion of the pivoted latch I35 has sliding pivotal movement.

The latch holder block III has a reduced threaded portion I33 integral therewith which slidably penetrates a transverse gate latch support bar I44 and is secured therein as by a nut I 15. The pivot pin I33 is oscillatably mounted in opposite walls of the notch I32 and has fixedly mounted thereon a latch control arm or knob I36 which is provided with a groove l36a. therein.

The knob I36 has a spring anchor I31 thereon. The spring anchor I I? is disposed forwardly of the pin I33 and has one end of a tension spring I53 connected thereto which extends rearwardly and is connected to a spring anchor I5I projecting from one side of the latch holder block MI. The spring anchors E41 and I 5| are so positioned with respect to each other that they would be in alinement with the pin I when the knob or control lever I46 projected outwardly in the plane of a line extending from the spring anchor through the pivot pin I40 and, consequently, the spring I50 will cause the control knob I46 to be urged either side of dead center relative to the pivot pin I40.

It is thus seen that when the control knob I is moved below dead center as shown in Figure 6, this knob urges the latch I35 rearwardly or in a clockwise direction until it engages the bottom of the slot or groove I42 in the latch holder block I4I, due to the lower edge of the bottom of the slot or groove I46a in the control knob engaging the front surface of the latch I35. The downward stroke of the latch I35 should be such that the hook I31 thereon moves out of engagement with the lower surface or with the upper wall of the slot or opening I34 in the gate I23 so the spring I50 may readily cause the latch I35 to move rearwardly at its lower end out of engagement with the gate I 23. The reason for moving the latch $35 to this inoperative position is to permit one of the gates I23 and I23 to be operated while the other of the gates remains inoperative in the event that only one of the trackways 35 or 35' has crackers, wafers or the like directed thereto.

Now, when it is desired to move the latch I35 to operative position as shown in Figures 1, 3 and 5, the control knob I46 is merely moved upwardly or in a counter-clockwise direction in Figure 6 to cause the lower end of the latch I35 to be urged forwardly or in a counter-clockwise direction in Figure 6 by the tension spring I59 thereby insuring that the latch I35 is urged towards and against the corresponding gate I 23. Thus, upon the next downward stroke of the latch I35, the hook I31 will enter the slot B4 in the gate I23.

The gate latch support bar I44 is disposed above the horizontal plane of the upper surfaces of the block 5I to 55, inclusive, and is also disposed forwardly of the lower portion of a suitable hopper I which is preferably made from sheet metal and only a portion of which is shown in Figures 1 and 3. The hopper is adapted to contain a supply of coating or filler material, indicated at F in Figures 8, 9 and 1G, and directs the same to the chamber 16 in the pump housing 69. The walls of the hopper I55 are suitably secured at their lower ends to flange members or angle bars I 56, as by welding, and these angle bars are, in turn, suitably secured to the upper surfaces of the blocks 5| to 55, inclusive, of the housing 50, as by screws I51. The blocks 5! to 55, inclusive, are provided with suitable threaded bores I60 for reception of the screws I51 as is clearly shown in Figure 2.

Opposite ends of the gate latch support bar I44 extend beyond the outer surfaces of the end or outside blocks 5I and 52 and are suitably secured, as by screws IBI, to the front ends of gate operating arms I62 and I53. The gate operating arms I62 and I63 extend rearwardly and are fixedly mounted on opposite ends of a shaft I65 oscillatably mounted in bearing blocks I65 and I66 which are suitably secured, as by screws I61, to the upper surfaces of respective bearing support members or bars I10 and HI. The upper surfaces of these bearing support members I15 and HI are preferably flush with the upper surfaces of the outside or end blocks 5i and 52 and 12 are suitably secured to the outer surfaces thereof, as by screws I12 (Figures 2 and 4).

It will be observed in Figures 1 and 2 that the shaft I64 extends outwardly beyond the gate operating arm I62 and has the rear end of a gate crank arm I15 fixed thereon which extends forwardly in substantially parallel relation to the gate operating arm I62 and has the upper portion of a gate crank arm link I16 pivotally mounted in the bifurcated front end thereof by means of a pin I11 which is threadably penetrated by the threaded upper portion of the gate crank arm link I16. The pin I11 is oscillatably mounted in the bifurcated front end of the gate crank arm I15. The upper end of the gate crank arm link I16 extends above the front end of the gate crank arm I15 and has a suitable control knob I fixed thereon which may be manipulated by an operator for rotating the gate crank arm link I16 for adjustment purposes and to thereby determine the distance that the gates I23 and I23 will be raised above the base plate BI (Figure 3) of the housing 50 each time a portion of the viscous filling material in the filling dispensing apparatus is to be discharged from beneath either one or both of the gates I23 and I23.

The lower end of the gate crank arm link I16 is slidably positioned within a link pilot member I8I and is held thereon by any suitable means, such as a spring clip I 82, which is an inverted U-shaped member preferably made from spring wire and having inwardly projecting outwardly curving portions at the lower end of each leg thereof which partially encircle the pilot member I8I and clampingly engage the same to thereby prevent the gate crank arm link I15 from being moved upwardly inadvertently.

The pilot member I8I extends downwardly and is pivotally mounted, as at I85, in the bifurcated rear end of a cam follower arm I86 which is pivotally mounted at its front end thereof, as at I 81, on the side frame member II of the frame Ill. The bifurcated rear end of the cam follower arm I has a suitable follower wheel or cam follower I90 rotatably mounted therein which is urged downwardly into engagement with the periphery of a cam wheel IEiI by any suitable means such as a tension spring I 92. The tension spring I92 is connected at its upper end to a spring anchor I93 projecting from the lower surface of the gate crank arm I 15, adjacent the front end thereof, and the lower end of the tension spring I92 is connected, as at I94, to the side frame member II of the frame I8.

The cam wheel I9I comprises juxtaposed disklike plates or cam wheel portions IIBIa and IQIb each having a low surface I95 and a high surface I95a. The cam I9I is an adjustable cam and the disk-like cam wheel portion I9Ia thereof has a slot I55 therein in which is mounted a screw I91 which is threadably embedded in the other half I9Ib of the adjustable cam I9I. Either one or both of the halves I9Ia and I9Ib of the cam I9I are fixed on one end of a cam shaft 200 which is supported and driven by any suitable means such as that shown in said co-pending application, Serial No. 236,617. Of course, the cam I9I is driven at a speed proportionate to the speed of movement of the main conveyor 21 so the gates I23 and I23 will be raised to opened position each time the leading edge of a cracker, wafer or the like W moves forwardly of the front edge of the base plate 6| of the dispensing apparatus (Figures 3, 8, 9 and 10). It is evident that the igh surfaces 195 on opposite halves of the cam 19! will move into engagement with the cam follower I80 as the leading edges of the crackers, wafers or the like W move beyond the front edge of the plate 6!. Thus, the link He moves upwardly and causes the latches I35 and I35 to move upwardly therewith for raising the gates H3 and I23.

Now, as either one or both of the gates I23 and 123 are moved. upwardly to the opened position, in which the gate I23 is shown in Figure 8, the viscous filling material or peanut butter, which has previously been forced against the inner surface of the lower portion of the gate 123 due to circulation of the peanut butter caused by the gears 82 and 83 (Figure 3), a portion of the viscous filling material or peanut butter, indicated at P in Figures 8, 9 and 10, is forced through the discharge opening I22 and between the lower edge of the gate I23 and the upper surface of the base plate El and, thus, passes downwardly by gravity to engage the wafer W adjacent the leading edge thereof. The viscous material will adhere to the upper surface of the wafer W as the wafer continues to move forwardly by means of the conveyor pins 33 and 35.

Now, as heretofore stated, the most important feature of the present invention is the particular manner in which the portion P of the filling material is separated from the bulk of the filling material F disposed within the housing 59. As the low surfaces its on each of the cam plates me and l lb of the cam it! move into engagement with the cam follower ace, the latches 135 and i255 are caused to move downwardly by means of the tension springs I32 (Figure 1) and the gates I23 and 523 are also caused to move downwardly to closed position due to the corresponding springs I31.

As the gate I23 moves downwardly, it gradually reduces the size of the opening between the lower of the gate and the upper surface of the case plate 6: and thereby squeezes or compresses the viscous material or peanut butter to cause the trailing edge of the portion P to be tapered. as is clearly shown in Figure 10, with the result that the portion of the filling material P is pinched off of the bulk of the filling material disposed within the housing 56 of the filling dispensing apparatus.

This pinching effect, caused by the lower edge the gate 523 pressing against the upper surface of the plate til at the front edge thereof, tapers the portion P of the filling material to such an extent that a substantially sharp trailing edge is provided thereon and with the result that none of the filling material in the portion P will cling to the gate 23 or to the plate i, Of course, with continued forward movement of the corresponding wafer W, the trailing edge of the portion P of the filling material P- will fall onto the wafer W thus completing the coating operation and after which a second wafer may be positioned upon the portion P of the filling material if so desired.

This unique method of separating the portion P of the filling material from the bull: thereof constitu es one of the most important factors contributing to the successful operation of sandwich making machines of the type shown in my co-pen-ding applications, since the sandwich or wafer coating machine with which a filling dispensing apparatus of the type described is employed may operate continuously for extended periods far surpassing the periods that similar machines have been able tooperate continuously heretofore without the necessity of stopping the machine periodically to clean the dispensing apparatus.

fhis method of separating the portion P of the filling material from the bulk thereof also results in a uniform coating being applied to each of the wafers W as they are successively passed beneath the filling dispensing apparatus and prevents any portion of the portion P of coating or filling material from clinging to the dispensing apparatus while the remaining portion thereof remains on the corresponding wafer W. Heretofore, in some instances, the entire extruded portion P of the filling material would cling to the dispensing apparatus and the corresponding particular wafer would be entirely devoid of any coating after it had moved past the filling dispensing apparatus, with the result that the sandwich making machine or wafer coating machine would have to be stopped and the wafer W removed from the machine or, if the wafer was permitted to continue through the machine, it would be necessary to again pass this particular wafer through the machine and this would also require that the strip or a portion of extruded filling material would have to be removed from the discharge opening of the filling dispensing apparatus of the type heretofore employed. The latter condition has been completely eliminated by the improved means for parting the viscous material.

In the drawings and specification, there has been set forth a preferred embodiment of the invention and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.

I claim:

1, In a machine for depositing a viscous coating material onto wafers and the like, coating depositing mechanism comprising a housing having a pair of rotatable shafts therein and a plurality of compartments through which the shafts pass, a pair of intermeshing gear wheels disposed in each compartment and fixed on said shafts, a discharge passageway leading from the bottom of each compartment and to one edge of the coating depositing mechanism, an intake cavity disposed above the gear wheels, a hopper disposed above the intake cavity into which coating material may be placed, means for imparting rotation to the gear wheels to deliver coating material through the discharge passageways, a slidable gate mounted on the housing for opening and closing each of the passageways, disengageable means for engaging the gates for imparting reciprocatory motion to the gates to ope-n and close the discharge passageways, means for selectively disconnecting the disengageable means from the gates to cause any one of the gates to remain inoperative, means for normally moving an inoperative gate to closed position, and said housing having a return passageway communicating with each of said discharge passageways and leading back into the intake cavity at a point immediately above the gear wheels whereby unused coating material will be returned into the intake cavity above the gear wheels when not discharged through the discharge passageway.

2. In a wafer coating machine, a coating dispensing apparatus comprising a gear pump having a plurality of discharge passageways and a return passageway leading from each of the discharge passageways back into the gear pump,

each of the discharge passageways having a discharge opening at one end thereof, a slidable gate fitting over each of the discharge openings, driven means for reciprocating said slidable gates to open and close said openings to allow a coating material to be passed therethrough, selectively operative means for rendering inoperative any one of said slidable gates without interfering with the other slidable gates, said selectively operative means comprising a vertically reciprocating horizontal bar spaced substantially above said gates and having a plurality of latches thereon, there being one of the latches for each of said gates, each of said gates having an opening adjacent the upper edge thereof, each of said latches having a hook portion on the lower end thereof adapted to lit in the opening in the corresponding gate, spring means normally urging the gates downwardly to closed position, means on said horizontal bar for pivotally supporting each of said latches and manually operable control means for varying the position of each of the latches about its axis whereby, upon movement of the control means in one direction, each of the latches will be in engagement with the opening in the corresponding gate and, upon moving any one of the control means in the other direction, one of the latches is swung out of the vertical plane of the corresponding gate thereby moving the hook thereon out of engagement with the opening in the corresponding gate to permit the latch to reciprocate with said bar without opening and closing the corresponding gate.

3. In a machine for depositing a viscous coating material onto wafers and the like, a viscous coating dispensing apparatus provided with at least one discharge passageway adjacent the lower portion thereof and also being provided with means for directing viscous material forwardly along said passageway under pressure; the combination of a relatively thin plate defining the bottom of the passageway and the bottom of the apparatus, a relatively thin gate normally closing the front end of said passageway and being positioned with its front surface substantially flush with the front edge of the plate defining the bottom of said passageway, said gate having a flat bottom edge normally resting upon the upper surface of the plate, automatically operable means for intermittently raising said gate a predetermined distance to thereby permit a portion of the viscous material to be extruded from the passageway between the lower surface of the gate and the upper surface of said plate and to permit the extruded portion of the viscous material to move downwardly by gravity, and means for moving the gate downwardly to ultimately press the bottom edge of the gate against the upper surface of the plate, whereby the fiat bottom edge of the gate pinches the viscous material against the upper edge of the plate to thus separate the extruded portion thereof from the portion thereof disposed in said passageway.

4. In a structure according to claim 3, means for supporting said gate comprising a gate support block secured to the front surface of said dispensing apparatus, guide plates disposed adjacent opposite side edges of said gate and against which the gate moves in sliding engagement, a gate confining plate secured against the guide plates, said guide plates being secured against the front surface of the gate support block, and the guide plates being of slightly greater thickness than the gate to permit free sliding movement of the gate.

5. In a wafer coating machine having a viscous coating material dispensing apparatus closely beneath and past whose front end wafers may be successively passed, said dispensing apparatus having at least one substantially horizontal passageway in its lower portion adapted to extend substantially parallel to the path of travel of the wafers and also having means for directing viscous material along said passageway under pressure toward the front end of the dispensing apparatus; the combination of a relatively thin member defining the bottom of said passageway, said memher having a flat substantially vertical front edge thereon, a relatively thin flat bottomed substantially vertically disposed gate normally closing the end of said passageway and having its fiat bottom normally resting upon the upper surface of said thin member and having its front surface disposed in substantially the same vertical plane as the front edge of said thin member, means operable automatically for raising said gate to provide an orifice between the lower ed e of said gate and the upper surface of the member to thereby permit the viscous material to be extruded through said orifice and whereby the viscous material may fall upon the upper surface of a wafer being passed therebeneath, spring means normally urging said gate downwardly to closed position, and means operable automatically for releasing said gate after it has been raised whereby said spring means will urge said gate to closed position and the gate will pinch the viscous material to separate the extruded portion thereof from the portion thereof disposed within the passageway for uniformly coating each successive Wafer.

6. In a machine for depositing a viscous coating material onto wafers and the like; coating depositing mechanism comprising a housing having a pair of rotatable shafts therein and a plurality of compartments through which the shafts pass, a pair of intermeshing gear wheels disposed in each compartment and fixed on said shafts, said housing having a discharge passageway leading from the bottom of each compartment and to one edge of the coating depositing mechanism, said housing also having an intake cavity disposed above the gear wheels and into which coating material may be placed, means for imparting rotation to the gear wheels to deliver coating material through the discharge passageways, a slidaole gate mounted on the housing for opening and closing each of the passageways, disengageable means for engaging the gates for imparting reciprocatory motion to the gates to open and close the discharge passageways, means for selectively disconnecting the disengageable means from the gates to cause any one of the gates to remain inoperative, means for normally moving an inoperative gate to closed position, and said housing having a return passageway communicating with each of said discharge passageways and leading back into the intake cavity at a point immediately above the gear wheels whereby unused coating material will be returned into the intake cavity above the gear wheels when not discharged through the discharge passageway.

7. In a machine for depositing a viscous coating material onto wafers and the like; coating depositing mechanism comprising a housing having a plurality of compartments therein, a pair of inermeshing gear wheels disposed in each compartment, said housing having a discharge passageway leading from the bottom of each compartment and to one edge of the coating depositing mechanism, said housing also having an intake cavity disposed above the gear wheels and into which coating material may be placed, means for imparting rotation to the gear wheels to deliver coating material through the discharge passageways, a slidable gate mounted on the housing for opening and closing each of the passageways, disengageable means for engaging the gates for imparting reciprocatory motion to the gates to open and close the discharge passageways, means for selectively disconnecting the disengageable means from the gates to cause any one of the gates to remain inoperative, means for normally moving any inoperative gates to closed position, and said housing having a return passageway communicating with each of said discharge passageways and leading back into the intake cavity at a point immediately above the gear wheels whereby unused coating material will be returned into the intake cavity above the gear wheels when not discharged through the discharge passageway.

8. In a wafer coating machine, a coating material dispensing apparatus having a plurality of discharge passageways, means for directing the coating material into the discharge passageways, said apparatus having a return passageway leading from each of the discharge passageways back into the apparatus, said apparatus having a discharge opening communicating with one end of each of the discharge passageways thereof, a slidable gate fitting over each of the discharge openings, driven means for reciprocating said slidable gates to open and close said openings to allow a coating material to be passed therethrough, selectively operable means for rendering inoperative any of said slidable gates without interfering with the remaining slidable gates, said selectively operable means comprising a vertically reciprocating substantially horizontal bar spaced above said gate and having a plurality of latches for each of said gates, each of said gates having an opening adjacent the upper edge thereof, each of said latches having a hook portion on the lower end thereof adapted to fit in the opening in the corresponding gate, spring means normally urging the gates downwardly to closed position, means on said horizontal bar for pivotally supporting each of said latches, and manually operable control means for varying the position of each of the latches about its axis whereby, upon move ment of the control means in one direction, each of the latches will be in engagement with the opening in the corresponding gate and, upon moving any one of the control means in the other direction, one of the latches is swung out of the vertical plane of the corresponding gate thereby moving the hook thereon out of engagement with the opening in the corresponding gate to permit the latch to reciprocate with said bar without opening and closing the corresponding gate.

9. In an apparatus for dispensing a viscous coating material onto wafers and the like, said apparatus having at least one discharge passageway formed in the lower portion thereof, means for directing viscous material forwardly along said passageway under pressure, and vertically reciprocable means disposed adjacent the front discharge end of said passageway; the combination of a relatively thin plate defining the bottom of said passageway and the bottom of said apparatus, a relatively thin flat gate for closing and opening the discharge end of said passageway and being connected to said vertically reciprocable means, the outer surface of said gate being flush with the front edge of said plate when the gate is in lowered closed position, and the lower surface of said gate being flat and parallel with the portion of the upper surface of the plate which is engageable thereby whereby the flat lower surface of the gate will pinch the viscous material against the upper surface of the plate to separate the extruded portion thereof from the portion thereof disposed in said passageway each time the gate is moved to closed position.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 771,560 Meurell Oct. 4, 1904 874,560 Berg Dec. 24, 1907 1,258,322 Doellinger Mar. 5, 1918 1,635,190 Michallat July 12, 1927 1,730,932 Glisce Oct. 8, 1929 2,108,771 Laird Feb. 15, 1938 2,246,758 Roth June 24, 1941 2,456,651 Schmiel Dec. 21, 1948 2,520,493 Curelee Aug. 29, 1950 

